The 1854 Nankai earthquake occurred at about 16:00 local time on 24 December, it had a magnitude of 8.4 and caused a damaging tsunami. More than 30,000 buildings were completely destroyed and there were at least 3,000 casualties.[1]

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The southern coast of Honshu runs parallel to the Nankai Trough, which marks the subduction of the Philippine Sea Plate beneath the Eurasian Plate. Movement on this convergent plate boundary leads to many earthquakes, some of them of megathrust type, the Nankai megathrust has five distinct segments (A–E) that can rupture independently,[2][3] the segments have ruptured either singly or together repeatedly over the last 1300 years.[4] Megathrust earthquakes on this structure tend to occur in pairs, with a relatively short time gap between them; in addition to the two events in 1854, there were similar earthquakes in 1944 and 1946. In each case the northeastern segment ruptured before the southwestern segment.[5]

The damage due to the earthquake was severe with 5,000 houses being destroyed and 40,000 houses badly damaged. A further 6,000 homes were damaged by fire, the tsunami washed away a further 15,000 houses and a total of 3,000 people died from either the earthquake or the tsunami.[6] The death toll associated with the tsunami was less than would be expected in comparison to the 1707 tsunami, because many people had left the coastal area following the large earthquake the previous day;[7] in Hiro (now Hirogawa), Goryo Hamaguchi set fires using rice straw to help guide villagers to safety. This story was turned into "A living god" by the Greek-born writer Lafcadio Hearn.[8]

On Shikoku, the greatest inundation heights were 7.5 m in Mugi, 7.5 m in Kamikawaguchi (Japanese: 上川口) of Kuroshio,[10] 7.2 m at Asakawa on the Tokushima coast, 7.4 m at Usa, 8.4 m at Ōnogō in the Susaki area, 8.3 m at Kure on the Kōchi coast and 5 m at both Hisayoshiura and Kaizuka on the coast of Ehime.[7]

1.
Coordinated Universal Time
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Coordinated Universal Time, abbreviated to UTC, is the primary time standard by which the world regulates clocks and time. It is within about 1 second of mean time at 0° longitude. It is one of closely related successors to Greenwich Mean Time. For most purposes, UTC is considered interchangeable with GMT, the first Coordinated Universal Time was informally adopted on 1 January 1960. This change also adopted leap seconds to simplify future adjustments, a number of proposals have been made to replace UTC with a new system that would eliminate leap seconds, but no consensus has yet been reached. Leap seconds are inserted as necessary to keep UTC within 0.9 seconds of universal time, see the Current number of leap seconds section for the number of leap seconds inserted to date. The official abbreviation for Coordinated Universal Time is UTC and this abbreviation arose from a desire by the International Telecommunication Union and the International Astronomical Union to use the same abbreviation in all languages. English speakers originally proposed CUT, while French speakers proposed TUC, the compromise that emerged was UTC, which conforms to the pattern for the abbreviations of the variants of Universal Time. Time zones around the world are expressed using positive or negative offsets from UTC, the westernmost time zone uses UTC−12, being twelve hours behind UTC, the easternmost time zone, theoretically, uses UTC+12, being twelve hours ahead of UTC. In 1995, the nation of Kiribati moved those of its atolls in the Line Islands from UTC-10 to UTC+14 so that the country would all be on the same day. UTC is used in internet and World Wide Web standards. The Network Time Protocol, designed to synchronise the clocks of computers over the internet, computer servers, online services and other entities that rely on having a universally accepted time use UTC as it is more specific than GMT. If only limited precision is needed, clients can obtain the current UTC from a number of official internet UTC servers, for sub-microsecond precision, clients can obtain the time from satellite signals. UTC is also the standard used in aviation, e. g. for flight plans. Weather forecasts and maps all use UTC to avoid confusion about time zones, the International Space Station also uses UTC as a time standard. Amateur radio operators often schedule their radio contacts in UTC, because transmissions on some frequencies can be picked up by many time zones, UTC is also used in digital tachographs used on large goods vehicles under EU and AETR rules. UTC divides time into days, hours, minutes and seconds, days are conventionally identified using the Gregorian calendar, but Julian day numbers can also be used. Each day contains 24 hours and each hour contains 60 minutes, the number of seconds in a minute is usually 60, but with an occasional leap second, it may be 61 or 59 instead

2.
International Seismological Centre
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1900–1912 J. Milne 1912–1917 H. H. Turner 1918–1931 H. H. Turner 1931–1939 H. Plaskett 1939–1952 Sir Harold Jeffreys 1952–1960 R. Stoneley 1960–1963 P. L. Willmore 1964–1970 P. L. Willmore 1970–1977 E. P. Willeman 2004–2007 A. Shapira 2008–present D. A. Storchak The main scientific goal of the Centre is the compilation of earthquake information. Since 1957 the manipulation of the volume of data has been mainly carried out by computer. Up until then ISS locations were determined manually with the help of a large globe, the ISC now uses a network of workstations accessing a relational database of nearly 50 Gbytes of online data. The analysis of the data is undertaken in monthly batches. During analysis the computer program first groups origin estimates from different agencies, in a typical month more than 200,000 station readings are analysed leading to an average of 10,000 events per month being identified, of which some 4,000 require manual review. Misassociations and other discrepancies are rectified and the remaining unassociated readings are searched for new events, the total number of events listed each month is several times greater than those obtained by any other worldwide location service and results from ISCs goal to provide a fully comprehensive list. This global instrumental earthquake catalogue, covering events for the period 1900–2009, was released in 2013 by the International Seismological Centre, the catalogue was prepared at the request of the GEM Foundation. Epicentral locations and hypocentral depths were recalculated from original travel time using a consistent velocity model. Sources Official website International Seismological Centre Bulletin – IRIS Consortium

3.
Richter magnitude scale
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The Richter magnitude scale assigns a magnitude number to quantify the size of an earthquake. As measured with a seismometer, an earthquake that registers 5.0 on the Richter scale has a shaking amplitude 10 times greater than an earthquake that registered 4.0 at the same distance. This means that, for instance, an earthquake of magnitude 5 releases 31.6 times as energy as an earthquake of magnitude 4. In the United States, the Richter scale was succeeded in the 1970s by the moment magnitude scale, the moment magnitude scale is now the scale used by the United States Geological Survey to estimate magnitudes for all modern large earthquakes. Richter derived his earthquake-magnitude scale from the apparent magnitude scale used to measure the brightness of stars and that fixed measure was chosen to avoid negative values for magnitude, given that the slightest earthquakes that could be recorded and located at the time were around magnitude 3.0. The Richter magnitude scale itself has no limit, and contemporary seismometers can register, record. M L was not designed to be applied to data with distances to the hypocenter of the earthquake that were greater than 600 km. Later, to express the size of earthquakes around the planet, Gutenberg and Richter developed a surface wave magnitude scale and these are types of waves that are recorded at teleseismic distances. The two scales were adjusted such that they were consistent with the M L scale and that adjustment succeeded better with the M s scale than with the M b scale. Each scale saturates when the earthquake is greater than magnitude 8.0, because of this, researchers in the 1970s developed the moment magnitude scale. The older magnitude-scales were superseded by methods for calculating the seismic moment, about the origins of the Richter magnitude scale, C. F. Richter said, I found a paper by Professor K. Wadati of Japan in which he compared large earthquakes by plotting the maximum ground motion against distance to the epicenter. I tried a similar procedure for our stations, but the range between the largest and smallest magnitudes seemed unmanageably large, dr. Beno Gutenberg then made the natural suggestion to plot the amplitudes logarithmically. I was lucky, because logarithmic plots are a device of the devil, the particular instrument used would become saturated by strong earthquakes and unable to record high values. The scale was replaced in the 1970s by the moment magnitude scale, for earthquakes adequately measured by the Richter scale, anything above 5 is classified as a risk by the USGS. Several scales have historically described as the Richter scale, especially the local magnitude M L. In addition, the body wave magnitude, m b, a couple of new techniques to measure magnitude are in the development stage by seismologists. All magnitude scales have been designed to give similar results

4.
Geographic coordinate system
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A geographic coordinate system is a coordinate system used in geography that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are chosen such that one of the numbers represents a vertical position. A common choice of coordinates is latitude, longitude and elevation, to specify a location on a two-dimensional map requires a map projection. The invention of a coordinate system is generally credited to Eratosthenes of Cyrene. Ptolemy credited him with the adoption of longitude and latitude. Ptolemys 2nd-century Geography used the prime meridian but measured latitude from the equator instead. Mathematical cartography resumed in Europe following Maximus Planudes recovery of Ptolemys text a little before 1300, in 1884, the United States hosted the International Meridian Conference, attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt the longitude of the Royal Observatory in Greenwich, the Dominican Republic voted against the motion, while France and Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911, the latitude of a point on Earths surface is the angle between the equatorial plane and the straight line that passes through that point and through the center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels, as they are parallel to the equator, the north pole is 90° N, the south pole is 90° S. The 0° parallel of latitude is designated the equator, the plane of all geographic coordinate systems. The equator divides the globe into Northern and Southern Hemispheres, the longitude of a point on Earths surface is the angle east or west of a reference meridian to another meridian that passes through that point. All meridians are halves of great ellipses, which converge at the north and south poles, the prime meridian determines the proper Eastern and Western Hemispheres, although maps often divide these hemispheres further west in order to keep the Old World on a single side. The antipodal meridian of Greenwich is both 180°W and 180°E, the combination of these two components specifies the position of any location on the surface of Earth, without consideration of altitude or depth. The grid formed by lines of latitude and longitude is known as a graticule, the origin/zero point of this system is located in the Gulf of Guinea about 625 km south of Tema, Ghana. To completely specify a location of a feature on, in, or above Earth. Earth is not a sphere, but a shape approximating a biaxial ellipsoid. It is nearly spherical, but has an equatorial bulge making the radius at the equator about 0. 3% larger than the radius measured through the poles, the shorter axis approximately coincides with the axis of rotation

5.
Tsunami
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A tsunami or tidal wave, also known as a seismic sea wave, is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Unlike normal ocean waves which are generated by wind, or tides which are generated by the pull of the Moon and Sun. Tsunami waves do not resemble normal undersea currents or sea waves, Tsunamis generally consist of a series of waves with periods ranging from minutes to hours, arriving in a so-called internal wave train. Wave heights of tens of metres can be generated by large events, numerous terms are used in the English language to describe waves created in a body of water by the displacement of water, however, none of the terms in frequent use are entirely accurate. The term tsunami, meaning harbour wave in literal translation, comes from the Japanese 津波, while not entirely accurate, as tsunami are not restricted to harbours, tsunami is currently the term most widely accepted by geologists and oceanographers. Tsunami are sometimes referred to as tidal waves and this once-popular term derives from the most common appearance of tsunami, which is that of an extraordinarily high tidal bore. Although the meanings of tidal include resembling or having the form or character of the tides, use of the tidal wave is discouraged by geologists. The term seismic sea wave also is used to refer to the phenomenon, prior to the rise of the use of the term tsunami in English-speaking countries, scientists generally encouraged the use of the term seismic sea wave rather than tidal wave. The Sumatran region is not unused to tsunamis either, with earthquakes of varying magnitudes regularly occurring off the coast of the island, Tsunamis are an often underestimated hazard in the Mediterranean Sea and parts of Europe. The tsunami claimed more than 123,000 lives in Sicily, the Storegga Slide in the Norwegian sea and some examples of tsunamis affecting the British Isles refer to landslide and meteotsunamis predominantly and less to earthquake-induced waves. The cause, in my opinion, of this phenomenon must be sought in the earthquake, at the point where its shock has been the most violent the sea is driven back, and suddenly recoiling with redoubled force, causes the inundation. Without an earthquake I do not see how such an accident could happen, the principal generation mechanism of a tsunami is the displacement of a substantial volume of water or perturbation of the sea. This displacement of water is attributed to either earthquakes, landslides, volcanic eruptions, glacier calvings or more rarely by meteorites. The waves formed in this way are then sustained by gravity, tides do not play any part in the generation of tsunamis. Tsunami can be generated when the sea floor abruptly deforms and vertically displaces the overlying water and they grow in height when they reach shallower water, in a wave shoaling process described below. A tsunami can occur in any state and even at low tide can still inundate coastal areas. On April 1,1946, the 8.6 Mw Aleutian Islands earthquake occurred with a maximum Mercalli intensity of VI and it generated a tsunami which inundated Hilo on the island of Hawaii with a 14-metre high surge. Between 165 and 173 were killed, the area where the earthquake occurred is where the Pacific Ocean floor is subducting under Alaska

6.
Ansei great earthquakes
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The Ansei great earthquakes were a series of three major earthquakes that struck Japan during the Ansei era. The Ansei Tōkai quake was an 8.4 magnitude earthquake struck on December 23,1854. The epicenter ranged from Suruga Bay to the ocean, and struck primarily in the Tōkai region. Over 10,000 people from the Tōkai region down to Kyushu were killed, the Ansei Edo quake was a 6.9 magnitude earthquake which struck Edo on November 11,1855. One hundred and twenty earthquakes and tremors in total were felt in Edo in 1854-55, the great earthquake struck after 10 oclock in the evening, roughly 30 aftershocks continued until dawn. The epicenter was near the mouth of the Arakawa River, records from the time indicate 6,641 deaths inside the city, and 2,759 injuries, much of the city was destroyed by fire, leading many people to stay in rural inns. This quake was a particularly destructive deep thrust quake caused by a giant slab of rock stuck between the Philippine Sea Plate and the Pacific Plate, the earthquake was blamed on a giant catfish thrashing about. Ukiyo-e prints depicting namazu became very popular around this time, other notable quakes to strike in the Ansei period include one in the Iga area, one which registered 7.4 on the Richter scale and struck Kyushu and Shikoku. The 1858 Hietsu earthquake struck the Hietsu area on April 9,1858, List of earthquakes in Japan List of historical tsunamis 河出書房新社編集部. Yokohama Burning, The Deadly 1923 Earthquake And Fire That Helped Forge the Path to World War II

7.
Nankai megathrust earthquakes
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In one recorded case the fault ruptured along its entire length. The area remains active, and future earthquakes are anticipated, with a high risk of a Nankai earthquake in the near future. The Nankai Trough is the expression of the subduction zone between the Philippine Sea and Amur plates. Honshu itself is formed from the island arc developed over the subducting plate, the megathrust boundary extends about 700 km from the southern end of Kyūshū to the triple junction with the Okhotsk Plate near Mount Fuji. At its southwestern end, there is another junction, where the overriding plate becomes the Okinawa Plate. The megathrust dip increases from about 5° near the surface to 10° as it passes beneath the coast of Honshu, analysis of seismic reflection data suggests that some of the displacement is carried by a splay fault dipping at about 25°. This megasplay fault system has caused a thick section of fluid-rich sedimentary rocks to be deeply underthrust. The presence of this zone may lead to shallow coseismic rupture along the megasplay faults during megathrust earthquakes. The Nankai megathrust is thought to have caused at least 12 major earthquakes in the last ca.1300 years, the pattern of historical seismicity reveals that the megathrust surface is segmented, with five separate zones of rupturing identified, conventionally labelled A–E, from west to east. Earthquakes involving the A+B segments are referred to as Nankai earthquakes, C+D Tonankai earthquakes. The earthquake repeat intervals are generally in the range 90–200 years, on all but one occasion, rupture of segment C has been followed by rupture of segments A+B within a few years. This behaviour has been reproduced by modelling the viscoelastic response of the megathrust fault plane with lateral variations in both convergence rate and frictional properties, the northeastern most part of the megathrust, segment E, has not ruptured since 1854. A future great earthquake involving rupture along this and possibly other segments has been proposed as a risk for the southern coast of Honshu. In 1999, the likelihood of the occurrence of a earthquake in the Tokai area in the period 2000-2010 was estimated to be in the range of 0.35. –0.45. Despite the uncertainty of when such an earthquake will occur, local authorities are taking action to prepare residents for what they regard as an inevitability

8.
Nankai Trough
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The Nankai Trough 南海トラフ is a submarine trough located south of the Nankaidō region of Japans island of Honshū, extending approximately 900 km offshore. In plate tectonics, the Nankai Trough marks a zone that is caused by subduction of the Philippine Sea Plate beneath Japan. This plate boundary would be an oceanic trench except for a high flux of sediments that fills the trench, within the Nankai Trough there is a large amount of deformed trench sediments, making one of Earths best examples of accretionary prism. Furthermore, seismic studies have revealed the presence of basement highs that are interpreted as seamounts that are covered in sediments. The northern part of the trough is known as the Suruga Trough, the Nankai trough runs roughly parallel to the Japan Median Tectonic Line. Conventional geologic estimates of plate movement velocities are difficult in the Nankai Trough because there are no spreading ridges that bound the tectonic plate and this area was not in the original NUVEL models. However, a recent study that included the Philippine Sea plate was based on data from the NUVEL-1A model. This study estimates that subduction in the Nankai Trough is about 43 mm/yr, rEVEL-based calculations indicate that there is no accumulation of strain at the trench. The rates of movement have been calculated to be in a range of 3.0 ±1.8 mm/yr to 11.1 ±1.7 mm/yr, as mentioned previously, the NUVEL-1A plate motion model does not include the Philippine Sea plate. This is because the mathematics of this only used twelve plates. However, using the Eurasia to North America plate motion, the rate was 2–4 mm/yr. This is not in agreement with the REVEL model, seemingly indicating that the NUVEL-1A model may need further revision, the deposits are primarily trench-wedge turbidites. There are indications of an increase in the retention of porosity within the rock, typically porosity reduces with increasing depth. However, there is a preservation of porosity at depth at drill site 1173. This has been attributed to post-depositional opal cementation that is preserving the porosity, the detrital clays, primarily smectite, display variation over time and location in the Nankai Trough as well as the Shikoku basin. At depth there is an increase in the clay content in the sediments. Furthermore, there is an alteration of the smectite, converting it to illite clay. The Nankai Trough is actively deforming and marks a region of seismic activity, deformation is concentrated in the outermost imbricate zone, with a significant amount of out of sequence thrusting occurring landward

9.
Subduction
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Subduction is a geological process that takes place at convergent boundaries of tectonic plates where one plate moves under another and is forced or sinks due to gravity into the mantle. Regions where this occurs are known as subduction zones. Rates of subduction are typically in centimeters per year, with the rate of convergence being approximately two to eight centimeters per year along most plate boundaries. Plates include both oceanic crust and continental crust, stable subduction zones involve the oceanic lithosphere of one plate sliding beneath the continental or oceanic lithosphere of another plate due to the higher density of the oceanic lithosphere. That is, the lithosphere is always oceanic while the overriding lithosphere may or may not be oceanic. Subduction zones are sites that have a rate of volcanism, earthquakes. Subduction zones are sites of convective downwelling of Earths lithosphere, subduction zones exist at convergent plate boundaries where one plate of oceanic lithosphere converges with another plate. The descending slab, the plate, is over-ridden by the leading edge of the other plate. The slab sinks at an angle of approximately twenty-five to forty-five degrees to Earths surface and this sinking is driven by the temperature difference between the subducting oceanic lithosphere and the surrounding mantle asthenosphere, as the colder oceanic lithosphere is, on average, denser. At a depth of approximately 80–120 kilometers, the basalt of the oceanic crust is converted to a rock called eclogite. At that point, the density of the oceanic crust increases and provides additional negative buoyancy and it is at subduction zones that Earths lithosphere, oceanic crust, sedimentary layers and some trapped water are recycled into the deep mantle. Earth is so far the only planet where subduction is known to occur, subduction is the driving force behind plate tectonics, and without it, plate tectonics could not occur. Subduction zones dive down into the mantle beneath 55,000 kilometers of convergent plate margins, subduction zones burrow deeply but are imperfectly camouflaged, and geophysics and geochemistry can be used to study them. Not surprisingly, the shallowest portions of subduction zones are known best, subduction zones are strongly asymmetric for the first several hundred kilometers of their descent. They start to go down at oceanic trenches and their descents are marked by inclined zones of earthquakes that dip away from the trench beneath the volcanoes and extend down to the 660-kilometer discontinuity. Subduction zones are defined by the array of earthquakes known as the Wadati–Benioff zone after the two scientists who first identified this distinctive aspect. Subduction zone earthquakes occur at greater depths than elsewhere on Earth, such deep earthquakes may be driven by deep phase transformations, thermal runaway, the subducting basalt and sediment are normally rich in hydrous minerals and clays. Additionally, large quantities of water are introduced into cracks and fractures created as the slab bends downward

10.
Philippine Sea Plate
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The Philippine Sea Plate or Philippine Plate is a tectonic plate comprising oceanic lithosphere that lies beneath the Philippine Sea, to the east of the Philippines. Most segments of the Philippines, including northern Luzon, are part of the Philippine Mobile Belt, to the north, the Philippine Sea Plate meets the Okhotsk Plate at the Nankai Trough. The Philippine Sea Plate, the Amurian Plate, and the Okhotsk Plate meet at Mount Fuji in Japan, thickened crust of the Izu-Bonin-Mariana arc colliding with Japan constitutes the Izu Collision Zone. The eastern side of the Philippine Sea Plate is a convergent boundary with the Pacific Plate subducting at the Izu-Ogasawara Trench, the east of the plate includes the Izu-Ogasawara and the Mariana Islands, forming the Izu-Bonin-Mariana Arc system. There is also a divergent boundary between the Philippine Sea Plate and the small Mariana Plate which carries the Mariana Islands, to the south, the Philippine Sea Plate is bounded by the Caroline Plate and Birds Head Plate. To the west, the Philippine Sea Plate subducts under the Philippine Mobile Belt at the Philippine Trench, to the northwest the Philippine Sea Plate meets Taiwan and the Nansei islands on the Okinawa Plate, and southern Japan on the Amurian Plate. List of earthquakes in Guam List of earthquakes in Japan List of earthquakes in the Philippines Hall, Robert, Fuller, Michael, Ali, Jason R. Anderson, the Philippine Sea Plate Magnetism and Reconstructions. High resolution map of Tectonic Plate Boundaries Map showing Seismicity of the Earth, 1900‒2012, Philippine Sea Plate and Vicinity United States Geological Survey

11.
Eurasian Plate
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It also includes oceanic crust extending westward to the Mid-Atlantic Ridge and northward to the Gakkel Ridge. The eastern side is a boundary with the North American Plate to the north and a boundary with the Philippine Sea Plate to the south, and possibly with the Okhotsk Plate and the Amurian Plate. The southerly side is a boundary with the African Plate to the west, the Arabian Plate in the middle, the westerly side is a divergent boundary with the North American Plate forming the northernmost part of the Mid-Atlantic Ridge, which is straddled by Iceland. The geodynamics of central Asia is dominated by the interaction between the Eurasian and Indian Plates, in this area, many subplates or crust blocks have been recognized, which form the Central Asian and the East Asian transit zones

12.
Convergent boundary
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As a result of pressure, friction, and plate material melting in the mantle, earthquakes and volcanoes are common near convergent boundaries. When two plates move towards one another, they form either a subduction zone or a continental collision and this depends on the nature of the plates involved. In a subduction zone, the plate, which is normally a plate with oceanic crust, moves beneath the other plate. During collisions between two plates, large mountain ranges, such as the Himalayas are formed. The nature of a convergent boundary depends on the type of plates that are colliding, at an oceanic-continental convergent boundary, the oceanic lithosphere will always subduct below the continental lithosphere. This is caused by the density difference between the oceanic and continental lithosphere. This type of boundary is called a subduction zone. At the surface, the expression is commonly an oceanic trench which forms on the oceanic side. On the continental side, a chain of volcanoes forms above the location of the subducting plate, an example of a continental-oceanic subduction zone is the area along the western coast of South America where the oceanic Nazca Plate is being subducted beneath the continental South American Plate. A volcanic arc is formed on the plate, above the location of the downgoing oceanic slab. The volcanic arc is the expression of the magma that is generated by hydrous melting of the mantle above the downgoing slab. The buoyant fluids then rise into the asthenosphere, where they lower the temperature of the mantle. Either action will create extensive mountain ranges and it may have also pushed nearby parts of the Asian continent aside to the east. When two plates with oceanic crust converge, they create an island arc as one plate is subducted below the other. The arc is formed from volcanoes which erupt through the plate as the descending plate melts below it. The arc shape occurs because of the surface of the earth. A deep oceanic trench is located in front of such arcs where the descending slab dips downward, plates may collide at an oblique angle rather than head-on to each other, and this may cause strike-slip faulting along the collision zone, in addition to subduction or compression. Not all plate boundaries are easily defined, some are broad belts whose movements are unclear to scientists

13.
Hirogawa, Wakayama
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Hirogawa is a town in Arida District, Wakayama Prefecture, Japan. As of 2016, the town had an population of 7,059. The total area is 65.35 km², thanks to the story Inamura no Hi, The Burning Rice Fields by Tsunezo Nakai and Lafcadio Hearns Gleanings in Buddha-Fields, Hirogawa is often referred to the home of A Living God, Goryo Hamaguchi. In 1854, Goryo Hamaguchi saved many lives from the struck the Kii Peninsula following the big earthquake. He set fires to rice sheaves to help guide those in danger to safety on the hilltop. He also devoted himself to help fellow villagers find jobs and build confidence by constructing a huge seawall, Goryo Hamaguchi and others established a private academy called Taikyu-sha to give the villagers the opportunity to learn. In 1907, George Trumbull Ladd, assisting Marquis Ito, visited the school, mr. Hearn, it appears, had never visited the locality, and, indeed, we were assured that we were the first foreigners who had ever been in the village streets. In Korea with Marquis Ito Media related to Hirogawa, Wakayama at Wikimedia Commons Hirogawa official website

14.
Lafcadio Hearn
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In the United States, Hearn is also known for his writings about the city of New Orleans based on his ten-year stay in that city. Hearn was born in and named after the island of Lefkada, one of the Greek Ionian Islands and he was the son of Surgeon-Major Charles Bush Hearn and Rosa Antoniou Kassimatis, a Greek woman of noble Kytheran lineage through her father, Anthony Kassimatis. His father was stationed in Lefkada during the British occupation of the islands, Lafcadio was baptized Patricios Lefcadios Hearn in the Greek Orthodox Church, but he seems to have been called Patrick Lefcadio Kassimati Charles Hearn in English. George Hearn died on 17 August 1850, two months after Lafcadios birth, in 1850 Hearns father was promoted to Staff Surgeon Second Class and was reassigned from Lefkada to the British West Indies. In 1852, he arranged to send his son and wife to live with his family in Dublin, Ireland, Charles Hearns mother, Elizabeth Holmes Hearn, had difficulty accepting Rosa Hearns Catholicism and lack of education. Despite Sarah Brenanes efforts, Rosa suffered from homesickness, when her husband returned to Ireland on medical leave in 1853, it became clear that the couple had become estranged. Charles Hearn was assigned to the Crimean Peninsula, again leaving his pregnant wife, when he came back in 1856, severely wounded and traumatized, Rosa had returned to her home island of Cerigo in Greece, where she gave birth to their third son, Daniel James Hearn. Lafcadio had been left in the care of Sarah Brenane, Charles Hearn petitioned to have the marriage with Rosa annulled, on the basis of her lack of signature on the marriage contract, which made it invalid under English law. After being informed of the annulment, Rosa almost immediately married Giovanni Cavallini, Cavallini required as a condition of the marriage that Rosa give up custody of both Lafcadio and James. As a result, James was sent to his father in Dublin, neither Lafcadio nor James saw their mother again, who had four children with her second husband. Rosa was eventually committed to the National Mental Asylum on Corfu, Charles Hearn, who had left Lafcadio in the care of Sarah Brenane for the past 4 years, now appointed her as Lafcadios permanent guardian. He married his sweetheart, Alicia Goslin, in July 1857, and left with his new wife for a posting in Secunderabad. Lafcadio never saw his father again, Charles Hearn died of malaria in the Gulf of Suez in 1866, in 1857, at age seven and despite the fact that both his parents were still alive, Hearn became the permanent ward of his great aunt, Sarah Brenane. She divided her residency between Dublin in the months, her husbands estate at Tramore, County Waterford on the southern Irish coast. Brenane also engaged a tutor during the year to provide basic instruction. Hearn began exploring Brenanes library and read extensively in Greek literature, Hearn became fluent in French and would later translate into English the works of Guy de Maupassant, who coincidentally attended the school shortly after Hearns departure. In 1863, again at the suggestion of Molyneux, Hearn was enrolled at St. Cuthberts College, Ushaw, in this environment, Hearn adopted the nickname Paddy to try to fit in better, and was the top student in English composition for three years. At age 16, while at Ushaw, Hearn injured his eye in a schoolyard mishap

15.
Kyushu
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Kyushu is the third biggest island of Japan and most southwesterly of its four main islands. Its alternative ancient names include Kyūkoku, Chinzei, and Tsukushi-no-shima, the historical regional name Saikaidō referred to Kyushu and its surrounding islands. In the 8th century Taihō Code reforms, Dazaifu was established as an administrative term for the region. As of 2016, Kyushu has a population of 12,970,479, the island is mountainous, and Japans most active volcano, Mt Aso at 1,591 metres, is on Kyushu. There are many signs of tectonic activity, including numerous areas of hot springs. The most famous of these are in Beppu, on the east shore, the island is separated from Honshu by the Kanmon Straits. The name Kyūshū comes from the nine ancient provinces of Saikaidō situated on the island, Chikuzen, Chikugo, Hizen, Higo, Buzen, Bungo, Hyūga, Osumi, excepting Oita and Miyazaki cities, the eastern seaboard shows a general decline in population. Designated cities Fukuoka Kitakyushu Kumamoto Core cities Kagoshima Ōita Nagasaki Miyazaki Naha Kurume Parts of Kyushu have a climate, particularly Miyazaki. Major agricultural products are rice, tea, tobacco, sweet potatoes, the island is noted for various types of porcelain, including Arita, Imari, Satsuma, and Karatsu. Heavy industry is concentrated in the north around Fukuoka, Kitakyushu, Nagasaki, and Oita and includes chemicals, automobiles, semiconductors, in 2010, the graduate employment rate in the region was the lowest nationwide, at 88. 9%. Besides the volcanic area of the south, there are significant mud hot springs in the part of the island, around Beppu. These springs are the site of occurrence of certain extremophile micro-organisms, the Kanmon Bridge also connects the island with Honshu. Railways on the island are operated by the Kyushu Railway Company, and Nishitetsu Railway

16.
Kansai region
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The Kansai region or the Kinki region lies in the southern-central region of Japans main island Honshū. The region includes the prefectures of Mie, Nara, Wakayama, Kyoto, Osaka, Hyōgo, while the use of the terms Kansai and Kinki have changed over history, in most modern contexts the use of the two terms is interchangeable. The urban region of Osaka, Kobe and Kyoto is the second most populated in Japan after the Greater Tokyo Area, the Kansai region is the cultural and historical heart of Japan with 11% of its land area and 22,757,897 residents as of 2010. In the north the region is bordered by the Sea of Japan, to the south by the Kii Peninsula and Pacific Ocean, four of Japans national parks lie within its borders, in whole or in part. The area also contains six of the seven top prefectures in terms of national treasures, other geographical features include Amanohashidate in Kyoto Prefecture and Awaji Island in Hyōgo. The Kansai region is compared with the Kantō region, which lies to its east and consists primarily of Tokyo. This East-West rivalry has deep roots, particularly from the Edo period. With a samurai population of less than 1% the culture of the merchant city of Osaka stood in sharp contrast to that of Edo, many characteristic traits of Kansai people descend from Osaka merchant culture. Catherine Maxwell, an editor for the newsletter Omusubi, writes, Kansai residents are seen as being pragmatic, entrepreneurial, down-to-earth and possessing a strong sense of humour. Kanto people on the hand are perceived as more sophisticated, reserved and formal, in keeping with Tokyo’s history and modern status as the nation’s capital. Kansai is known for its food, especially Osaka, as supported by the saying Kyotoites are ruined by overspending on clothing, popular Osakan dishes include takoyaki, okonomiyaki, kitsune udon and kushikatsu. Kyoto is considered a mecca of traditional Japanese cuisine like kaiseki, Kansai has many wagyu brands such as Kobe beef and Tajima cattle from Hyōgo, Matsusaka beef from Mie and Omi beef from Shiga. Sake is another specialty of the region, the areas of Nada-Gogō, as opposed to food from Eastern Japan, food in the Kansai area tends to be sweeter, and foods such as nattō tend to be less popular. The dialects of the people from the Kansai region, commonly called Kansai-ben, have their own variations of pronunciation, vocabulary, Kansai-ben is the group of dialects spoken in the Kansai area, but is often treated as a dialect in its own right. Kansai is one of the most prosperous areas for baseball in Japan, two Nippon Professional Baseball teams, Hanshin Tigers and Orix Buffaloes, are based in Kansai. Koshien Stadium, the stadium of the Hanshin Tigers, is also famous for the nationwide high school baseball tournaments. In association football, the Kansai Soccer League was founded in 1966, cerezo Osaka, Gamba Osaka, and Vissel Kobe belong to J. League Division 1 and Kyoto Sanga F. C. belongs to J. League Division 2, the top professional leagues in Japan. The terms Kansai, Kinki, and Kinai have a deep history

17.
Japanese language
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Japanese is an East Asian language spoken by about 125 million speakers, primarily in Japan, where it is the national language. It is a member of the Japonic language family, whose relation to language groups, particularly to Korean. Little is known of the prehistory, or when it first appeared in Japan. Chinese documents from the 3rd century recorded a few Japanese words, during the Heian period, Chinese had considerable influence on the vocabulary and phonology of Old Japanese. Late Middle Japanese saw changes in features that brought it closer to the modern language, the standard dialect moved from the Kansai region to the Edo region in the Early Modern Japanese period. Following the end in 1853 of Japans self-imposed isolation, the flow of loanwords from European languages increased significantly, English loanwords in particular have become frequent, and Japanese words from English roots have proliferated. Japanese is an agglutinative, mora-timed language with simple phonotactics, a vowel system, phonemic vowel and consonant length. Word order is normally subject–object–verb with particles marking the grammatical function of words, sentence-final particles are used to add emotional or emphatic impact, or make questions. Nouns have no number or gender, and there are no articles. Verbs are conjugated, primarily for tense and voice, but not person, Japanese equivalents of adjectives are also conjugated. Japanese has a system of honorifics with verb forms and vocabulary to indicate the relative status of the speaker, the listener. Japanese has no relationship with Chinese, but it makes extensive use of Chinese characters, or kanji, in its writing system. Along with kanji, the Japanese writing system uses two syllabic scripts, hiragana and katakana. Latin script is used in a fashion, such as for imported acronyms. Very little is known about the Japanese of this period, Old Japanese is the oldest attested stage of the Japanese language. Through the spread of Buddhism, the Chinese writing system was imported to Japan, the earliest texts found in Japan are written in Classical Chinese, but they may have been meant to be read as Japanese by the kanbun method. Some of these Chinese texts show the influences of Japanese grammar, in these hybrid texts, Chinese characters are also occasionally used phonetically to represent Japanese particles. The earliest text, the Kojiki, dates to the early 8th century, the end of Old Japanese coincides with the end of the Nara period in 794

18.
Tokushima Prefecture
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Tokushima Prefecture is a prefecture of Japan located on Shikoku island. The capital is the city of Tokushima, until the Meiji Restoration, Tokushima Prefecture was known as Awa Province. In ancient times, Tokushima City belonged to a known as Myōdō-gun. In the first wave of government consolidation following the abolishment of the system and construction of prefectures in 1871. At the time, it included the Awa region to the south, in 1873 it further incorporated the region currently occupied by Kagawa Prefecture in its borders. In the second wave of government consolidation, on September 5,1875, on August 21,1876, Awaji Island separated to join Hyogo Prefecture and the Awa region separated to form Kochi Prefecture. On March 2,1880, Myodo Prefecture fully separated from Kochi Prefecture to be inaugurated as Tokushima Prefecture,1945 August – End of World War II. The Washi no Mon gate to Tokushima Castle is destroyed by fire,1946 December – The Nankai earthquake occurs, causing vast damage throughout the prefecture. 1947 May – Naruto City is inaugurated,1949 May – Tokushima University is created. 1951 June – Komatsushima City is inaugurated,1958 May – Anan City is inaugurated. 1959 April – Shikoku Hoso begins TV broadcasts,1960 May – A tsunami caused by a quake in Chile causes damage in the prefectures south. 1961 April – The Short Term Womens College in Tokushima is opened,1961 July – The Lesser Naruto Bridge is opened in the Lesser Naruto Straits. 1963 April – The Tokushima Municipal Culture Center is completed,1963 July – A new thermal electric power plant is created in Anan. 1967 January – Construction of the Tokushima Airport terminal is completed,1970 August – Construction of the Koboke Dam on the Yoshino River is terminated. 1972 January – Use of a railway connecting the towns of Itano,1972 July – Construction of Route 11 over the Yoshino River Ohashi is completed. 1973 April – A railway is opened connecting the Mugi and Kaifu regions,1974 October – Tokushima-born Takeo Miki is elected as Prime Minister of Japan. 1975 March – Construction of the Ikeda Dam over the Yoshino River is completed,1976 July – A ceremony is held to celebrate the beginning of construction for the Onaruto Bridge. 1981 October – The National University Naruto Kyoiku Daigaku is opened,1982 August – Ikeda Highschool takes first place in the 64th National Baseball Championships

19.
Ehime Prefecture
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Ehime Prefecture is a prefecture in northwestern Shikoku, Japan. Until the Meiji Restoration, Ehime Prefecture was known as Iyo Province, since before the Heian period, the area was dominated by fishermen and sailors who played an important role in defending Japan against pirates and Mongolian invasions. After the Battle of Sekigahara, the Tokugawa shogun gave the area to his allies, including Kato Yoshiaki who built Matsuyama Castle, the name Ehime comes from the kuniumi part of the Kojiki where Iyo Province is mythologically named Ehime lovely princess. In 2012, a group from the University of Tokyo. Located in the part of Shikoku, Ehime faces the Seto Inland Sea to the north and is bordered by Kagawa and Tokushima in the east. The prefecture includes both high mountains in the region and a long coastline, with many islands in the Seto Inland Sea. The westernmost arm of Ehime, the Sadamisaki Peninsula, is the narrowest peninsula in Japan, chemical industries, oil refining, paper and cotton textile products also are a feature of the prefecture. Rural areas mostly engage in agricultural and fishing industries, and are known for citrus fruits such as mikan and iyokan. Ikatas nuclear power plant produces a portion of Shikokus electricity. Ehime University Ehime Prefectural University of Health Science St. Catherine University Matsuyama University Matsuyama Shinonome College The sports teams listed below are based in Ehime, baseball Ehime Mandarin Pirates The oldest extant hot spring in Japan, Dogo Onsen, is located in Matsuyama. It has been used for two thousand years. Iyo dialect, one of the Shikoku dialects, is the dialect spoken in Ehime Prefecture, ISBN 978-0-674-01753-5, OCLC58053128 Official website

20.
Shanghai
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Shanghai is the most populous city proper in the world, with a population of more than 24 million as of 2014. As one of the four direct-controlled municipalities of the Peoples Republic of China, it is a financial centre and transport hub. Located in the Yangtze River Delta in East China, Shanghai sits on the edge of the mouth of the Yangtze in the middle portion of the eastern Chinese coast. The municipality borders the provinces of Jiangsu and Zhejiang to the north, south and west, as a major administrative, shipping and trading city, Shanghai grew in importance in the 19th century due to trade and recognition of its favourable port location and economic potential. The city was one of five treaty ports forced open to foreign trade following the British victory over China in the First Opium War, the subsequent 1842 Treaty of Nanking and 1844 Treaty of Whampoa allowed the establishment of the Shanghai International Settlement and the French Concession. The city then flourished as a center of commerce between China and other parts of the world, and became the financial hub of the Asia-Pacific region in the 1930s. However, with the Communist Party takeover of the mainland in 1949, trade was limited to other socialist countries, and the citys global influence declined. In the 1990s, the reforms introduced by Deng Xiaoping resulted in an intense re-development of the city, aiding the return of finance. The two Chinese characters in the name are 上 and 海, together meaning Upon-the-Sea. The earliest occurrence of this dates from the 11th-century Song Dynasty, at which time there was already a river confluence. There are disputes as to exactly how the name should be understood, Shanghai is officially abbreviated 沪 in Chinese, a contraction of 沪渎, a 4th- or 5th-century Jin name for the mouth of Suzhou Creek when it was the main conduit into the ocean. This character appears on all motor vehicle license plates issued in the municipality today, another alternative name for Shanghai is Shēn or Shēnchéng, from Lord Chunshen, a third-century BC nobleman and prime minister of the state of Chu, whose fief included modern Shanghai. Sports teams and newspapers in Shanghai often use Shen in their names, such as Shanghai Shenhua F. C. Huating was another early name for Shanghai. In AD751, during the dynasty, Huating County was established at modern-day Songjiang. Today, Huating appears as the name of a hotel in the city. The city also has various nicknames in English, including Pearl of the Orient, during the Spring and Autumn period, the Shanghai area belonged to the Kingdom of Wu, which was conquered by the Kingdom of Yue, which in turn was conquered by the Kingdom of Chu. During the Warring States period, Shanghai was part of the fief of Lord Chunshen of Chu and he ordered the excavation of the Huangpu River. Its former or poetic name, the Chunshen River, gave Shanghai its nickname of Shen, two important events helped promote Shanghais development in the Ming dynasty

21.
China
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China, officially the Peoples Republic of China, is a unitary sovereign state in East Asia and the worlds most populous country, with a population of over 1.381 billion. The state is governed by the Communist Party of China and its capital is Beijing, the countrys major urban areas include Shanghai, Guangzhou, Beijing, Chongqing, Shenzhen, Tianjin and Hong Kong. China is a power and a major regional power within Asia. Chinas landscape is vast and diverse, ranging from forest steppes, the Himalaya, Karakoram, Pamir and Tian Shan mountain ranges separate China from much of South and Central Asia. The Yangtze and Yellow Rivers, the third and sixth longest in the world, respectively, Chinas coastline along the Pacific Ocean is 14,500 kilometers long and is bounded by the Bohai, Yellow, East China and South China seas. China emerged as one of the worlds earliest civilizations in the basin of the Yellow River in the North China Plain. For millennia, Chinas political system was based on hereditary monarchies known as dynasties, in 1912, the Republic of China replaced the last dynasty and ruled the Chinese mainland until 1949, when it was defeated by the communist Peoples Liberation Army in the Chinese Civil War. The Communist Party established the Peoples Republic of China in Beijing on 1 October 1949, both the ROC and PRC continue to claim to be the legitimate government of all China, though the latter has more recognition in the world and controls more territory. China had the largest economy in the world for much of the last two years, during which it has seen cycles of prosperity and decline. Since the introduction of reforms in 1978, China has become one of the worlds fastest-growing major economies. As of 2016, it is the worlds second-largest economy by nominal GDP, China is also the worlds largest exporter and second-largest importer of goods. China is a nuclear weapons state and has the worlds largest standing army. The PRC is a member of the United Nations, as it replaced the ROC as a permanent member of the U. N. Security Council in 1971. China is also a member of numerous formal and informal multilateral organizations, including the WTO, APEC, BRICS, the Shanghai Cooperation Organization, the BCIM, the English name China is first attested in Richard Edens 1555 translation of the 1516 journal of the Portuguese explorer Duarte Barbosa. The demonym, that is, the name for the people, Portuguese China is thought to derive from Persian Chīn, and perhaps ultimately from Sanskrit Cīna. Cīna was first used in early Hindu scripture, including the Mahābhārata, there are, however, other suggestions for the derivation of China. The official name of the state is the Peoples Republic of China. The shorter form is China Zhōngguó, from zhōng and guó and it was then applied to the area around Luoyi during the Eastern Zhou and then to Chinas Central Plain before being used as an occasional synonym for the state under the Qing

22.
Chi (unit)
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The chi is a traditional Chinese unit of length. It first appeared during Chinas Shang dynasty approximately 3000 years ago and has since adopted by other East Asian cultures such as Japan, Korea. In its ancient and modern forms, the chi is divided into 10 smaller units known as cun and 10 chi together form one zhang, in the Peoples Republic of China chi has been defined since 1984 as exactly 1/3 of a meter, i. e. 33 1⁄3 cm. However, in the Hong Kong SAR the corresponding unit, pronounced chek in Cantonese, is defined as exactly 0.371475 m, the two units are sometimes referred to in English as Chinese foot and Hong Kong foot. In Taiwan, chi is the same as the Japanese shaku, even earlier, during the Warring States era, the value of chi was essentially the same. It is thought that the ancient Chinese astronomers also used chi as an angular unit, in the 19th century, the value of chi, depending on the part of the country and the application, varied between 31 and 36 cm. In Guangzhou, however, the chi used for local trade varied from 14.625 to 14.81 inches – i. e. very close to the modern chek. The value fixed by a Sino-British treaty for the purposes of customs duties in Hong Kong was 14.1 inches, due to its long history and its widespread usage, chi has also seen metaphorical usages in the Chinese language. For example, chi cun, a made up of the units chi and cun, refers to the dimensions of an object. In informal use, it is sometimes used to refer to the US or imperial foot

23.
Huangpu River
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It is the last significant tributary of the Yangtze before it empties into the East China Sea. The Bund and Lujiazui are located along the river, the Huangpu is the largest river in Shanghai, with Suzhou Creek being its major tributary. It is on average 400 metres wide and 9 metres deep and it divides the city into two regions, Pudong and Puxi. Songpu Bridge Xupu Bridge Lupu Bridge Nanpu Bridge Yangpu Bridge Many lines of the Shanghai Metro cross underneath the river, there are also many tunnels crossing under the river. There are currently several ferry lines operated by Shanghai Ferry, in March 2013, thousands of pig carcasses were found floating in the Huangpu River in Shanghai. Some of the pigs carried ear tags saying they were from Jiaxing, so that city in Zhejiang may be the source, geography of China List of rivers in China Sladen, Douglas, Bits of China, The Japs at Home, 5th ed. New York, New Amsterdam Book Co. pp. 276–354

24.
International Standard Book Number
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The International Standard Book Number is a unique numeric commercial book identifier. An ISBN is assigned to each edition and variation of a book, for example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, the method of assigning an ISBN is nation-based and varies from country to country, often depending on how large the publishing industry is within a country. The initial ISBN configuration of recognition was generated in 1967 based upon the 9-digit Standard Book Numbering created in 1966, the 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108. Occasionally, a book may appear without a printed ISBN if it is printed privately or the author does not follow the usual ISBN procedure, however, this can be rectified later. Another identifier, the International Standard Serial Number, identifies periodical publications such as magazines, the ISBN configuration of recognition was generated in 1967 in the United Kingdom by David Whitaker and in 1968 in the US by Emery Koltay. The 10-digit ISBN format was developed by the International Organization for Standardization and was published in 1970 as international standard ISO2108, the United Kingdom continued to use the 9-digit SBN code until 1974. The ISO on-line facility only refers back to 1978, an SBN may be converted to an ISBN by prefixing the digit 0. For example, the edition of Mr. J. G. Reeder Returns, published by Hodder in 1965, has SBN340013818 -340 indicating the publisher,01381 their serial number. This can be converted to ISBN 0-340-01381-8, the check digit does not need to be re-calculated, since 1 January 2007, ISBNs have contained 13 digits, a format that is compatible with Bookland European Article Number EAN-13s. An ISBN is assigned to each edition and variation of a book, for example, an ebook, a paperback, and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, a 13-digit ISBN can be separated into its parts, and when this is done it is customary to separate the parts with hyphens or spaces. Separating the parts of a 10-digit ISBN is also done with either hyphens or spaces, figuring out how to correctly separate a given ISBN number is complicated, because most of the parts do not use a fixed number of digits. ISBN issuance is country-specific, in that ISBNs are issued by the ISBN registration agency that is responsible for country or territory regardless of the publication language. Some ISBN registration agencies are based in national libraries or within ministries of culture, in other cases, the ISBN registration service is provided by organisations such as bibliographic data providers that are not government funded. In Canada, ISBNs are issued at no cost with the purpose of encouraging Canadian culture. In the United Kingdom, United States, and some countries, where the service is provided by non-government-funded organisations. Australia, ISBNs are issued by the library services agency Thorpe-Bowker

25.
Plate tectonics
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The theoretical model builds on the concept of continental drift developed during the first few decades of the 20th century. The geoscientific community accepted plate-tectonic theory after seafloor spreading was validated in the late 1950s, the lithosphere, which is the rigid outermost shell of a planet, is broken up into tectonic plates. The Earths lithosphere is composed of seven or eight major plates, where the plates meet, their relative motion determines the type of boundary, convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along plate boundaries. The relative movement of the plates typically ranges from zero to 100 mm annually, tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle, the material lost is balanced by the formation of new crust along divergent margins by seafloor spreading. In this way, the surface of the lithosphere remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle, earlier theories, since disproven, proposed gradual shrinking or gradual expansion of the globe. Tectonic plates are able to move because the Earths lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the ridge and drag, with downward suction. Another explanation lies in the different forces generated by forces of the Sun. The relative importance of each of these factors and their relationship to other is unclear. The outer layers of the Earth are divided into the lithosphere and asthenosphere and this is based on differences in mechanical properties and in the method for the transfer of heat. Mechanically, the lithosphere is cooler and more rigid, while the asthenosphere is hotter, in terms of heat transfer, the lithosphere loses heat by conduction, whereas the asthenosphere also transfers heat by convection and has a nearly adiabatic temperature gradient. The key principle of plate tectonics is that the lithosphere exists as separate and distinct tectonic plates, Plate motions range up to a typical 10–40 mm/year, to about 160 mm/year. The driving mechanism behind this movement is described below, tectonic lithosphere plates consist of lithospheric mantle overlain by either or both of two types of crustal material, oceanic crust and continental crust. Average oceanic lithosphere is typically 100 km thick, its thickness is a function of its age, as passes, it conductively cools

26.
Amurian Plate
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The Amurian Plate is a minor tectonic plate in the northern and eastern hemispheres. It covers Manchuria, the Korean Peninsula, Western Japan, once thought to be a part of the Eurasian Plate, the Amur Plate is now generally considered to be a separate plate moving southeast with respect to the Eurasian Plate. The Amurian Plate is named after the Amur River, that forms the border between the Russian Far East and Northeastern China, the Baikal Rift Zone is considered a boundary between the Amurian Plate and the Eurasian Plate. GPS measurements indicate that the plate is slowly rotating counterclockwise, the Amurian Plate may have been involved in the 1976 Tangshan earthquake in China. Determination of the Amurian Plate Motion, mantle Dynamics and Plate Interactions in East Asia, Geodynamics Series. V.27, edited by M. F. J. Flower et al